Learning Activities: What Color Am I?
Suggested Grades 2-6

Concepts
Adaptation, camouflage, defense, predators
Identification of various anuran species found in Minnesota

Time
30-45 Minutes

Catalyst Question
How does the color of a frog help its survival?

Background
The skin of amphibians is important to their survival. It performs many functions including camouflage, protection, and a warning to predators. Many frogs and toads are dark green, brown, or black. This tone is produced by melanin, a dark pigment. These frogs usually blend in with their surroundings and their skin serves as a camouflage. Other anurans are brightly colored. If the bright colors alternate with dark splotches the coloring may serve as a warning to predators that the frog or toad is poisonous. Other frogs and toads are not poisonous but have a colorful skin that the predators associate with the poisonous varieties. Consequently, predators will often avoid these species. Other anurans have bright red or yellow markings on the undersides of their limbs that they display when in danger. The fire-bellied toad has this ability called the "unken reflex" to flash a colorful spot at a predator.

Amphibians have two kinds of color responses. Amphibians in the larval stage will blanch in darkness. The second other color response is when amphibians shift colors to match their backgrounds as a form of protection. In a couple of hours a Tree Frog can change from a vivid green, through a pattern of gray and green blotches, to a pale ash gray with dark markings. These changes don't necessarily harmonize with the frog's surroundings. Usually, they are a reaction to temperature. Other frogs, such as the gray tree frog, can adjust their color according to changes in light, moisture, chemicals and temperature.

Objectives
After completion of this activity students will be able to:

1. Identify various species of anurans by their skin coloration
2. Describe how coloration contributes to survival.

Materials
Sketches of Minnesota frogs from the 'Thousand Friends of Frogs' newsletter or the website located at: http://cgee.hamline.edu/frogs/science/mnfrogs.html

'The Toads and Frogs of Minnesota' poster produced by the Department of Natural Resources or the "Frogs as Bio-Indicators' Science Corner of the 'Thousand Friends of Frogs' website located at: http://cgee.hamline.edu/frogs/science/index.html

Crayons, markers or colored pencils

Procedure
1. Have the students color the sketches found on the website or in the 'Thousand Friends of Frogs' newsletter.
2. When they are finished the students should share their pictures with their classmates.
3. Students can practice identifying the various frogs and toads by their coloration.

Evaluation/Review Questions
What type of area would you find the frogs and toads you just colored?
Did you color them the same as they actually appear? Why or why not?
Why are frogs and toads colored the way they are?

Extensions
Students can research and compare the coloration of frogs from different biomes. Is there a correlation between habitat conditions and the coloring of the anurans?

References and Resources
Eyewitness Books. 1993. Amphibian. New York: Alfred A. Knopf.

National Wildlife Federation. 1987. Ranger Rick's Nature Scope: Let's Hear it for Herps. Washington, DC: National Wildlife Federation.

Stebbins, Robert C. and Nathan W. Cohen. 1997. A Natural History of Amphibians. Princeton, NJ: Princeton University Press.

Internet Resources
http://cgee.hamline.edu/frogs
http://www.flmnh.ufl.edu/natsci/herpetology/mamphrep.htm http://www.xmission.com/~gastown/herpmed/amphibia.htm

Education Standards
Click here for more information on how this activity correlates with standards.

Minnesota

6 Science Application (Living Systems)
National
Content Standard C Life Science (organisms and environments)
Environmental
Strand 2.2 The Living Environment

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